L4 will only run for about 500 hours??

[lionken07]

I was told by a friend and a few people on here that the L4 LED will only be good for around 500 hours. Most LED I've seen will go for thousands and thousands of hours. Is it true? if so why is that? is it overdriven that much?

I've also been told that 25% of the power in the L4 is release as heat (yeah that's probably true since it gets so hot after 10 mins of running it).

Someone please tell me the truth behind all these rumors /ubbthreads/images/graemlins/confused.gif

 

[paulr]

The early 5 watt Luxeons had a limited lifetime because of their high power dissipation. They may have improved by now. The failure mode is they get dimmer and dimmer. You shouldn't have to worry about your L4 suddenly going poof. Also, 500 hours is a lot of runtime for a light like an L4 (500 sets of batteries, which is over $1000 worth of batteries right there). Finally, if your L4 does dim significantly due to LED aging, Surefire's warranty should cover an LED replacement.

The L4 will have energy losses in both the dc/dc converter and the LED. Contrary to popular belief, the LED's efficiency is only about the same as an incandescent bulb. However, in an incan bulb, the wasted energy gets emitted out the front as near-infrared. With an LED, it goes into heating up the flashlight, which is why high-powered LED flashlights get hot.

 

[Klaus]

This horse has been beaten to death on this forum

YES - Surefire as all other manufacturers too so far is only able to use the parts Lumiled has or makes avaiable - those are the so-called "portable" 5W devices with the 500/1000h stigma. As soon as Lumileds releases a "non-portable" 5W LS Surefire is expected to use those then.

Surefire Customer Service claimed 5000h for the device which is probably due to its slightly underdriven usage below its maximum operating conditions.

All LEDs and especially the high powered LS emitters do produce heat - not in the beam as incandescents do but through the die of the LED itself. This is not limited to Surefire but a feature of those LEDs.

So all those stated issues are not rumours but facts - but still nothing to blame Surefire for as it is as it is with LEDs these days and Surefire while being on the cutting edge of those technologies still can´t defy the physics.

Use the search function to get a better idea on this

Klaus

 

[torment]

I wouldn't be worried even with 500 hours....that is so much time running a flashlight.

 

[Spango]

I was told by a rep in Surefire that the life expectancy is approximately 10.000 hours. I wonder if that means 10 hours, or was the person trying to say 10,000 hours? /ubbthreads/images/graemlins/thinking.gif

 

[CM]

The truth is somewhere between 10 hours and 10,000 hours. Seriously, I've tried to make a similar point paulr did using replacement bulbs used. Even 500 hours, compare that to 20 hours for the claimed life of a high performance Xenon bulb which cost $20. That's 25 bulb changes at $20 each is $500 in bulbs you'd be spending. Consider also that by the time 500 hours roll by, the light would probably be obsolete, having been replaced by 250 Lumen LED's that get two hours runtime on a pair of 123's /ubbthreads/images/graemlins/grin.gif

CM

CM

 

[Beretta1526]

/ubbthreads/images/graemlins/dedhorse.gif /ubbthreads/images/graemlins/poke2.gif /ubbthreads/images/graemlins/smoker5.gif

Oh, and as I'm just having fun, /ubbthreads/images/graemlins/grinser2.gif

 

[lionken07]

yeah somwhere deep down I just wanted to make sure. Of course 500 hours will be more than enough. if not we can always send it to surefire and they will most likely send you a new one.

 

[llvo]

why beat the horses?

is it an idiom or something? /ubbthreads/images/graemlins/confused.gif

 

[V8TOYTRUCK]

We beat a dead horse for topics that have been dicussed way too many times.

 

[Steelwolf]

It is an idiom. To beat a dead horse.

The idea of beating a horse is to get it to run faster, work harder, etc. But what is going to happen if you beat a dead horse? Nothing! /ubbthreads/images/graemlins/smile.gif (Maybe RSPCA officers will come and question you or something.) /ubbthreads/images/graemlins/tongue.gif

Basically, this topic is one of those few that have been discussed to death and still nothing can be done about it. You live with it or you don't. Those that do, realise that 500hrs is still a lot of time, especially in a flashlight. Unlike say a room light or window display light, it would be doubtful if a flashlight saw 20hrs a week, especially in typical civilian use.

And after 500hrs, it is only half as bright as when new, so it is still useable. Most flashoholics would probably have swapped out to brighter LEDs before the half-life is up anyways.

 

[mporter]

A dead horse to old timers here, but to newbies who are wanting to learn as much about flashlights as they can it's a fascinating and informative thread.

Even if this information might have been available by searching past posts I wouldn't have searched for it. I had the crude impression from other things I had read that LEDs (unless overdriven) have much longer lifetimes. I didn't know 5 watt Luxeons were so much shorter lived.

CPF is incredibly interesting to the new flashalolic. I appeal to you old-timers to bear with us. It's OK with us if you discuss the same old subject again. There's always a new perspective. And the technology moves so fast that knowledge gets dated quickly.

It's an honor just to lurk and listen here.

 

[BC0311]

[ QUOTE ]
mporter said:
A dead horse to old timers here, but to newbies who are wanting to learn as much about flashlights as they can it's a fascinating and informative thread.

Even if this information might have been available by searching past posts I wouldn't have searched for it. I had the crude impression from other things I had read that LEDs (unless overdriven) have much longer lifetimes. I didn't know 5 watt Luxeons were so much shorter lived.

CPF is incredibly interesting to the new flashalolic. I appeal to you old-timers to bear with us. It's OK with us if you discuss the same old subject again. There's always a new perspective. And the technology moves so fast that knowledge gets dated quickly.

It's an honor just to lurk and listen here.

[/ QUOTE ]

Well said, mporter.

The beating-a-dead-horse Graemlin is sometimes used by impatient posters to try to shut someone up or just to give vent to their impatience.

No one is twisting my arm to read anything on CPF. If I'm not interested or it's boring to me I just scroll on down.

In the originating post of this thread and paulr's reply, I didn't see anything that "blamed" Surefire at all. But, it really doesn't matter to me if it did.

Some members are overly sensitive to anything that can be construed as criticism of their "brand". I have to confess that I can be like this.

Maybe not so much with a "brand", since I like certain lights from several different brands. But, I can be overly sensitive when I think one of my "pet ideas" is being criticized.

I have a print on the wall above my monitor that helps remind me to be patient and stay /ubbthreads/images/graemlins/cool.gif (cool)...if I will just remember to stop, breathe, relax and look up at it. /ubbthreads/images/graemlins/tongue.gif

The problem with idiomatic expression is that it's idiomatic, and therefore easily misconstrued. /ubbthreads/images/graemlins/grin.gif

BC

 

[Badbeams3]

Not to rain on the parade...but does anyone know that Surefire will replace the light at some unknown "to dim point"? I might be inclined to think they would only warranty complete failure.

We all assume the 5 watters will loose 10% of its brightness for every 100 hours of use...1% every 10 hours.

BUT this could be way wrong...could loose 20% of its brightness in the first 10 hours of use...and loose less per hour after that. Sort of look like a brightness, run time chart...for a Photon...drop fast at first...then levels out somewhat.

It might not be a linear drop/loss /ubbthreads/images/graemlins/popcorn.gif

 

[llvo]

understood
Thanks V8TOYTRUCK and Steelwolf! /ubbthreads/images/graemlins/wink2.gif